Fluid compressor and the like



March 20, 1951 F. BERRY FLUID COMPRESSOR AND THE LIKE 5 Sheets-Sheet 1 Filed Aug. 21, 1946 INVENTOR. EPA/VKBERRY A TTORNEY March 20, 1951 F. BERRY FLUID COMPRESSOR AND THE LIKE 5 Sheets-Sheet 2 Filed Aug. 21, 1946 INVENTOR.

FfiAA/KBERRY ATTORNEY March 20, 1951 F. BERRY FLUID COMPRESSOR AND THE LIKE 5 Sheets-Sheet 5 Filed Aug. 21, 1946 INVENTORQ AA/KBEFPRY AT TORNEY March 20, 1951 F. BERRY 2,545,600

FLUID COMPRESSOR AND THE LIKE Filed Aug. 21, 1946 5 Sheets-Sheet 4 INVENTOR.

ATTORZSZEY March 20, 1951 Filed Aug. 21, 1946 FIG. IO

F. BERRY FLUID COMPRESSOR AND THE LIKE 5 Sheets-Sheet 5 INVENTOR. /-7?,4/v/r BER/P) A TTOENEY Patented Mar. 20, 1951 FLUID COMPRESSOR AND THE LIKE Frank Berry, Corinth, Miss., assignor to Berry Motors, Inc., Corinth, Miss., a corporation of Tennessee Application August 21, 1946, Serial No. 692,002

Claims.

The invention relates to rotary fluid energy transforming devices such as air compressors or motors. It has special application to rotary compressors or motors of the rotary abutment type.

It is a leading object of my invention to provide an improved construction and arrangement of the pistons, rotary abutments and casing members of devices of the class described to secure high operating eificiency, simplicity of construction, and low manufacturing cost.

A further object is to provide a rotary compressor having a pressure-balanced discharge which will equalize pressure on both sides of the rotary abutment and thereby reduce end thrust.

Other objects and advantages of my invention will appear as the description proceeds.

In the drawings, which illustrate certain preferred embodiments of the invention:

Fig. 1 is a side elevational view of a single stage refrigerator compressor, and Fig. 2 is a bottom view thereof, taken as indicated at 2--2 in Fig. 1. In both of these views the hermetic shell in which the unit is encased is shown in cross section so as to reveal the general construction of the compressor and its operating motor.

Fig. 3 is a central vertical cross sectional view of the same unit, taken on the line 3-3 of Fig. 1.

Figs. 4., 5, 6, 7 and 8 are detail cross sectional views taken as indicated in Fig. 3 on the lines 44, 55, 6-6, 'l-'| and 88, respectively.

Fig. 9 is a central vertical cross sectional view similar to Fig. 3, illustrating, as another embodiment of my invention, a multi-stage Freon compressor suitable for use in refrigeration.

Fig. 10 is a side elevational view of this multistage compressor with its encasing hermetic shell shown in cross section.

Fig. 11 is an end elevational view of the same unit, taken as indicated at H-|I in Fig. 9.

The preferred form of my invention is well illustrated in its adaptation to single or multistage refrigerator compressors, so I have selected these for specific description. I have selected, further, refrigeration units in which the compressor and its operating motor are direct-connected and adapted for mounting in an hermetically sealed shell for dust-free operation either at atmospheric or superatmospheric pressures. This is by way of illustration only, and it will be understood that the invention is useful for many other applications.

The single stage compressor unit shown in Figs. 1 to 8, inclusive, comprises an electric motor 2 I2 direct-connected to a compressor l3, the unit being mounted in a two-part shell l4, 15, carried by a suitable mounting bracket I6.

The compressor [3 comprises in its general arrangement longitudinally spaced casing members l1 and I8 (Figs. 1 and 3) forming the end walls of an annular cylinder chamber 19 and of an adjacent abutment chamber (Fig. 8), and a spacer casing member 2!! therebetween forming the outer peripheral walls of the cylinder and abutment chambers, a piston rotor comprising a shaft 2| and a piston 22 fixed thereto as by a key 21, and a rotary abutment 23 parallel to the shaft of the piston rotor having a recess 24 to clear the piston as it passes the abutment.

One of the important features of my construction is concerned with the form of the outer periphery of the rotary abutment 23 which, adjacent the edges of the piston recess 24 therein, is curved inwardly at 26 for sealing engagement with the piston. In my preferred construction the piston member surrounds the shaft Zljas shown clearly in Fig. 8, having a circular portion 25 28 and straight portions adjoining the circular portion. The rotary abutment 23 has a circular portion for rolling contact with the circular portion 28 of the piston rotor, and the inwardly curved portions 26 between the circular portion of the abutment and the piston recess M'therein provide sealing engagement with the straight portions 29 of thepis'ton member.

It will be observed that the spaced casing members i! and'lB have opposed surfaces lying substantially entirely in a single plane and that the spacer casing member 20 has parallel surfaces lying substantially entirely in a single plane for engagement with the opposed surfaces of the spaced casing members I! and I8; further, that the piston 22 and rotary abutment 23 have coplanar flat parallel ends lying adjacent the opposed surfaces of the spaced casing members. This arrangement makes it'possible to machine and finish-grind the end walls of the piston and abutment chambers and the adjacent flat surfaces of the piston and abutment without the use of any special tools or fixtures because all the surfaces are perfectly fiat and there are no projections on the piston or on any of the casing members l1, l8 and 20.

The three casing members l1, l8 and 2B are secured together, as by means of bolts 30 and machine screws 3! passing through aligned apertures therein, the latter having threaded engageinent with the casing member I1. I prefer asaaeoo 22 but in the opposite direction. Thus as viewed in Fig. 8 the piston 22 rotates in a clockwise di rection and the abutment 23 in a counter-clockwise direction.

The gears 35, 36 are enclosed'by acoverplate or housing 39 secured to the casing member l8 as by means of screws 40 passing through the flange 4| of the housing 39. housing 39 in the manner shown in Fig. 7 to provide a gear pump lubricating the compressor as will be described further. on. A short tube 42 projectsufromthezend of the gear;.housing. 3,9 to

provide-lcommunication between. the interior: .zof,

the housing and. a point well below the'rsurface oflrthee oilrcontained in .the hermetic: shell [4, E5.

casinglmembersyll andlearebored-at 4'41 and 45irtoereceivero-tor shaft 2| and the shaft 43 of rotary: abutment 23.;respectively. Abutment 23 may be'formed integrally with its shafts-3 or may berformed:-,separately and fixed-itheretozras will be described more particularly-with reference totheilmodifi'edconstructionillustrated in Figs-,9 to

11.: :The;;top.:casing member. I], is'formed with an extension. to. support-the armature ll of motor I251; Immy: preferredconstruction; casing mem benrl-Talsog is form-edas an integral .part'of the housing for motor l2, having later,a-lgl ,--and-up wardlywextending;brackets: 458' supporting-an: an-

nular-housingzmember 49 to receive the mounting: ring; .5flswhichecarries.the stator, of the motor.-

The stator '5 I #may have-a press'fit'in the-mountingeringszill. sand-ythe; latter .apress fitin the -annulanhousin :member. 49. Further; the housing 4951mm :have a-press. fl-t-in the-upper shell =54.

The-top casingmember I? and rits-extension 45 areproyided' with an :annular oil chamber. 52qsur-- roundin .the rotor I shaft. {and with an enlargedbore' -5 3 iat-theuppenend: of .theeXtension; also forilubricatin 011.1. Theflowerpart iii of theshell serves'-.as-;a reservoir for lubricating-.oilrwhich is drawn in through the;tube 42 at the-bottom of the; compressor by gthe-gear-pump 35, 36 from which it is forced throu hz-channelways fi lpfi a ofgthe:

pumpehousingflFig. 2) to thelower endsz-o-f the rotorandabutment shafts 2i and 4 From Ethe. lower .end Dfffihe; rotor shaft: 2f the oilqis forcedthrough ia central boreeeand thence through a transverse bore--51; r Transverse .borerill-leads to the annular chamber 52%fr0m; which-the oil ,is

carried upwardly by a spiral groove 59 in theshaft. 2L: Atitsupper end spiral groove 59 dies charges-oil intoythe annular recess 53 for 1ubrica-. tioniof'stheiqthrust bearing 6!) of the armature.-

Fromrthe transversebore. 58'; oil is discharged into, depression; 6.: I ,(Fig? .8) :in.. the: rotor. shaft. for lubrication betweena-thea-ends'ofthe piston 22.;and-

side wallsfof the-annulareyhnder l9; -':Oi1:is discharged fromthec-hamber52'through an aperture 62* into a .reservoir 63 "at I the top of the compressor fiformed by an upwardly extending rib 64 which at its ends adjoins extension at "of the casing member. Oil" fromathe reservoir 63 flows into" a central bore fit atthe upper end of the rotor'ashaft 43 and-thence through a transverse bore 66 ato an annular groove fil forlubricationof the: upper endf the abutment shaft; 3 Addie.

The gears. 35,1 36 fit the :1

tional lubrication of the upper end of this shaft is provided by a bore 68 (Fig. 6). The lower end of abutment shaft 43 receives oil through the central bore 69 and transverse bore 10. Excess oil overflows from the reservoir 63 and runs back into the main reservoir at the bottom shell l5.

An important feature of the lubricating system I have disclosed is thatit provides .gmeans for introducing oilat the inlet side of the-cylinder and abutment chambers as at 6| so that oil is drawn into the compressor on the suction side, and effective lubrication of the piston and cylinder walls is secured notwithstanding the elevated pressures resulting-from the action of the compressor.

Top casingmember I 1 is provided with an inlet passage, .1! counterbored to receive an intake tube 12 extending within the field win-ding 5! of the motor (Figs. 3 and 6). The fluid to be compressed is drawn into the hermetic shell through an. aperture. -73 at --its upper end; and; on

itsiway to-ithe intak tube 72 passes throughthe; clearance 74 betweemthe rotorand stator ofthemotor, assistingin coolingtheunit.

The spacer casing;;member;-;20 is apertured at let passage'll at such'times: asthe fiuidis not being drawn into thelcompressor The casing members- [land. iii :are. I provided with fluid outlets or exhaust; ports; .19,, 83 lead ing from the abutment chamber 25 opposite; each end. of the rotary, abutmentin the opposedsurfaces of the spacedcasingmemberst These ex,

haust ports, lead intotransverse-bores -8i, 82.

Transverse bore 82 in casingmember l8 isstoppedofiibya plug 83,-.whereas-ttransverse bore t ia -in casing member ll is counterbored to receive the end. of :a coupling-8;!connected-to discharge tube- 85 for-the compressedfluids. .This discharge tube leads through an opening Bean the shelMFig-Z). Aligned bores -in the threecasingmembers form .a connecting passageway 81- between the transverse bores 8| and 82, connecting thefluidoutlets '19,.- at oppositesidesof .the abutment chamber to a common discharge. The. provisionv of fluid outlets "inithe. abutment chamber opposite each end of. the rotary abutment in theopposed surfacesyof'the spaced casing members: I 1, l8 lequalizes thepressureat the-two endspf. the abutment; thereby reducingend thrust.

It is believed that the operation of the coma is drawn into theshell of the unit at -'l3,'passes through the clearance. between. the rotor; and

stator oflthe motor at 1 3;'-intal e"tube .72;,'and passagesl'l, i5 and-lepwhere'it is drawninto' therspace behind "the'piston. Asthe piston nears the end of its stroke, abutmentt23'uncoVers the fluid 'outlets'l 'ifli and the compressed fluid passes outof-the cylinder-ateach-side of abut-- W n t :ra tsm r .them sitionr shown in Figure 8:, the ;compression strolrebegins;v Fluid ahead-of the. :piston is compressedagainst' the abutment 2 3 :which; has :sealing engagement with ;the:piston; as Shawn. Fluid-to becompressedment chamber and flows through passages 8|, .82, 81 into the discharge tube 85. The piston then passes through the clearance recess 24 of the abutment and a new stroke is begun. Sealing contact between the piston and abutment is maintained by contact between one of the straight side portions 29 of the piston and the corresponding inwardly curved portion 26 of the abutment until such time as the cylindrical portions of the piston and abutment are brought into rolling contact, and thereafter the other straight side portion 29 of the piston is brought into contact with the inwardly curved portion 28 at the other side of the abutment until the piston is ready to enter the recess 24 of the abutment.

Reference will now be had to Figs. 9, 10 and 11 illustrating, as another embodiment of my invention, a multi-stage Freon compressor suitable for use in refrigeration. The unit comprises an electric motor 90 direct-connected to a compressor 9|, the unit being mounted in a two-part hermetically sealed shell 92, 93 carried by suitable mounting brackets 94, 95.

The compressor 9| comprises, in its general arrangement, spaced casing members 96, 91 and 98 forming the end walls of annular cylinder chambers and adjacent abutment chambers, spacer casing members 99 and I 00 therebetween forming the outer peripheral walls of the cylinders and abutment chambers, a piston .rotor comprising a shaft IOI and pistons I02and I03 fixed thereto, and rotary abutments I04 and I05 parallel to the shaft of the piston rotor having recesses I06, I01 to clear the pistons as they pass the abutments. the abutment shaft I08 as by means of pins I09. The abutment recesses I06, I01 may extend part way into the shaft I08 as indicated in Fig. 9 for recess I01. Abutments I04 and I05 are each of the same thickness as the cooperating pistons I02, I03 and have coplanar fiat parallel ends lying adjacent the opposed surfaces of the spaced casing members. As described in connection with the single stage compressor of Figs. 1 to 8, inclusive, this arrangement makes it possible to machine and finish-grind the end walls of the piston and abutment chambers and the adjacent flat surfaces of the pistons and abutments without the use of any special tools and fixtures because all the surfaces are perfectly flat and there are no projections on the piston or abutments, or on any of the casing members 96, 91, 98, 99, I00. In this embodiment, the motor housing member I I1 is formed separately from the casing member 96 although this is not essential.

Means for lubricating the unit may be provided similar to the means described with reference 'to Figs. 1 to 8, inclusive, utilizing the gearing between the shafts WI and I08 as a gear pump, indicated generally at IIO, to draw oil from the reservoir provided by the bottom of the shell 92, 93 through tube III. In the construction here shown the unit is mounted horizontally so that there is no overflow reservoir corresponding to the reservoir 63 shown in 3. However, excess oil passes out through the opening H6 between the motor and compressor. Also,'there is a discharge directly from the gear pump casing through a tube H2 (Fig. 11) which discharges over the top of the compressor, this overflow discharge preventing the building up of excess pressure by the gear pump, while assuring a steady flow of the lubricant.

The casing members and motor housing are fastened together in any suitable manner such as The abutments I 04, I 05 are secured to r by the means described with reference to the single stage compressor of Figs. 1 to 8, inclusive.

Operation of this unit is essentially the same as that described with reference to Figs. 1 to 8, inclusive, except, of course, that connecting passages must be provided between the two annular cylinders of the compressor. The fluid-intake, shown at I I8, communicates with the first stage cylinder in a manner similar to that illustrated in Fig. 8. The discharge from the first stage cylinder passes through outlet H3 in the abutmerit recess I01, flowing through the shaft I08 to a passage in the casing member 96, which in similar fashion communicates with the inlet of the second cylinder. From the second cylinder, the compressed gases are discharged from the abutment recess through an opening in the shaft !09 to an outlet I I4 which in turn discharges into a passage in the casing member 96 through a muffler I! 5 therein, and finally is discharged to the space within the shell 92, 93 through asuitable opening in member 95. This particular unit is designed for operation at elevated pressures; i. e. the pressure within the shell 92, 93 is that of the compressed gases. A suitable outlet for the compressed gas is provided at I I9, to which a fluid conduit may be connected as desired.

The terms and expressions which I have employed are used in a descriptive and not a limiting sense, and I have no intention of excluding such equivalents of the invention described, or of portions thereof, as fall within the purview of the claims.

I claim:

1. A rotary fluid energy transforming device comprising longitudinally spaced casing members forming the end walls of an annular cylinder chamber and a spacer casin member therebetween forming the outer peripheral wall of said cylinder chamber, a piston rotor comprising a shaft and a piston member surrounding the shaft and fixed thereto, the piston member having a circular portion concentric with the shaft and straight portions tangent to said circular portion, a rotary abutment parallel to the shaft of the piston rotor having a circular portion for rolling contact with the circular portion of the piston rotor and a reces to clear the piston as it passes the abutment, the abutment also having inwardly curved portions between its circular portion and the piston recess therein, said inwardly curved portions providing sealing engagement with said straight portions of the piston member when the circular portions of the piston member and abutment are out of contact.

2. A rotary fluid energy transforming device comprising longitudinally spaced casing members formin the end walls of an annular cylinder chamber and a spacer casing member therebetween forming the outer peripheral wall of said cylinder chamber, a piston rotor comprising a shaft and a piston member surrounding the shaft and fixed thereto, .the piston member having a circular portion concentric with the shaft and straight portions tangent to said circular portion, a rotary abutment parallel to the shaft of the piston rotor having a circular portion for rolling contact with the circular portion of the piston rotor and a recess to clear the piston as it passes the abutment, the abutment also having inwardly curved portions between its circular portion and the piston recess therein, said inwardly curved portions proacetate viding sealing engagement with said straight portions-of the, piston member when the circularportions of the piston member and abutment are out of contact, the piston member and rotary abutment having coplanar flat parallel ends lying adjacent the end walls of said casing members.

A rotary fluid energy transformin device comprising casing member forming adjacent cylinder and rotary abutment chambers, a piston rotor comprising a shaft and a piston member surrounding the shaft and fixed thereto, the piston member having a circular portion concentric with the shaft and straight portions tangent to said circular portion, a rotary abutment parallel tothe shaft of the piston rotor having a circular portion for rolling contact with. the circular portion of the piston rotor and a recess to clear the piston as it passes the abutment, the, abutment also having inwardly curved portions between its circular portion and the piston recess therein, said inwardly curved portions providing sealing engagement with said straight portions of the piston member when the circular portions of the piston member and abutment are out of contact.

4. A rotary fluid energy transforming device comprising casing members forming adjacent cylinder and rotary abutment chambers, a piston rotor comprising a shaft and a piston fixed thereto, a rotary abutment parallel to the shaft of the piston rotor having a recess to clear the piston as it passes ,the abutment, a fiuid inlet to the cylinder chamber at one side of the rotary abutment and fluid outletsin the abutment chamber opposite each end of the rotary abutment at the other side of the rotary abutment, and a .bore positioned to introduce oil at a point between the ends of the piston and the end walls of the cylinder chamber toward the suction side of the cylinder and abutment chambers.

cylinder and rotary abutment chambers, a piston rotor comprising'a shaft and a piston fixed thereto, a rotary abutment parallel to the shaft of the piston rotor having a'recess to clear the piston as it passes the abutment, a fluid inlet to the cylinder chamber at one side of the ro-' tary abutment and a fluid outlet in the abut- 10 ment chamber at its other side, and a bore positioned to introduce oil at a point between the ends of the piston and the end walls of the cylinder chamber toward the suction side of the cylinder and abutment chambers.

F. BERRY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED S'IfA'lES PATENTS Number Name Date 137,057 Chapman Mar. 25, 1873 310,053 Harrington Dec. 30, 1884 363,739 Frost May 24, 1887 525,532 Clement Sept. 4, 1894 795,777 Laxton July 25, 1905 1,072,155 Pearson Sept. 2, 1913 1,264,032 Easton Apr. 23, 1918 1,283,614 Alvey Nov. 5', 1918 1,365,245 Hutgreen Jan. 11, 1921 1,451,859 Balcker Apr. 17, 1923 1,834,976 Schmidt Dec. 8, 1931 2,062,035 McCormack -Nov.24, 1936 FOREIGN PATENTS Number Country Date 33,087 Germany Oct. 22, 1885 70,521 Sweden Oct. 28, 1930 40 610,729 France June 14, 1926 

